* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
.box {
  width: 300px;
  height: 200px;
  background-color: #AB69D9;
  margin: 200px auto;
  position: relative;
  z-index: 9;
}
.box .top {
  width: 50px;
  height: 50px;
  background-color: #AB69D9;
  border: 2px solid rgba(255, 255, 255, 0.5);
  border-top: 2px solid #fff;
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  border-radius: 50%;
  animation: move 1s infinite linear;
}
@keyframes move {
  to {
    transform: translate(-50%, -50%) rotate(360deg);
  }
}
